Electrode for arc-lamps.



- Rom-swing.

UNITED STATES PATENT OFFICE.

WILLIAM BOY MOTT, OF LAKEWOOD, OHIO, ASSIGN OR TO NATIONAL CARBON COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF NEW JERSEY.

ELECTRODE ron Ans-Limes.

To all whom it may concern: Be it known that I, WILLIAM ROY Mon,

a citizen of the United States, residing at I Lakewood, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Electrodes for Arc-Lamps, of which the following is a full, clear, and exact description.

This invention relates to electrodes for use in arc lamps, and more particularly in flaming arc lamps, the object being to produce an electrode which will imparta desired color to the arc stream and insure a nonflickering, steady light, as well as insure a field of light of great intensity and volume. Theseresults I obtain by the use of titanium in chemical combination with other suitable substances.

I am aware that titanium has heretofore been used as an ingredient for an are light electrode, the same being disclosed in United States Patents Nos. 421,469, and 422,302. These patents disclose the use of titanium in the form of titanic iron, which as is well known, contains titanium oxid.

My invention distinguishes from the disclosures in these patents in that I use titanium in the form of a titanate of a metal belonging to the group of alkaline earth elements, such as calcium, barium, strontium, zinc, etc., or a metal belonging to thegroup of rare earth elements, which include cerium, lanthanum, didyum, thorium, etc. I have also found it advantageous to use two or more titanates of difi'erent metals to form a part of the same electrode mixture, becauseof the decreased tendency to form a slag.

The advantages to be-obtained by the use of a titanate or titanates, are increased when the titanate is mixed with a fluorid of a metal belonging to either the group of alka- Specification of Letters Patent.

Patented Nov. 2,1, 1916.

Application tiled November 8, 1911. Serial No. 659,203.

velops the greatest candle power under comparative conditions.

With a cored carbon using as a filling mixture calcium fluorid, calcium titanate and calcined carbon under like conditions and tests, the following results were obtained with electrodes containing the proportions of the materials as stated below, The whiteness, steadiness and volume of light are considerably greater with the mix-' ture than when using their constituents separately.

M. S. C. P. denotes mean spherical candle power.

It has heretofore been found that flaming arc electrodes giving a substantially white light have been obtained at a sacrifice of candle power, while I have found that an electrode having as ingredients therein the materialsheretofore mentioned in the specification, has an increased candle power, and at the same time produces a substantially White light. As will be seen from the above table, electrodes Nos. 2 and 3 producing a substantially white light, give a candle power greatly in excess of electrode No. 1, which produces a color substantially the same as the ordinary yellow flaming electrode, and the candle power of these electrodes 2 and 3 is also greater than electrode No. 4, which produces a substantially white light.

The carbon used may be any of the well known forms, as calcined lamp black, coke,

coal, graphite, orcharcoal with tar. It also I may be of advantage to use potassium salts as a part of the mix, as it is well known that such salts assist in securing a steady burn mg.

The carbon, titanate and fluorid and such other substances as it may be desired to in corporate are thoroughly mixed together with a binder, such as pitch or analogous substance. This mixture is'forced through dies to produce electrodes of the desired form orthe electrodes may be molded. The

electrodes are then baked in suitable furnaces.

It may be desirable to use the titanate and forced into the core of the shell carbon in any desired manner.

The titanates and disclosed may be such as are synthetically prepared, or as these materials occur, in nature, as for instance, peroskite which is fluorids used as herein mineral calcium titanate, or monazite sands, which carry the rare earths. V

Having thus described, my invention, what I claim is:

1. An arc lamp electrode containing va rare-earth titanate. r

2. An arc lamp electrode containing car- -bon and rare-earth titanates.

In testimony whereof, I hereunto affix my signature in the presence of two witnesses. Y

WILLIAM ROY MOTT. Witnesses:

A.. J.'HUnsoN,

R. SULLIVAN. 

